Dura-Ace BR-7800 brakes question

[Keith A]

I have a friend who stripped off his Dura-Ace 9-speed parts and is building it up again with the Dura-Ace 10-speed group. He saw on the Shimano (http://dura-ace.shimano.com/publish/content/duraace/en/home/the_product0/braking.html) website that the brakes are now specific to the front and rear and was wondering how to tell them apart. He stated that the pair he received had the same length brake bolt and that there didn't appear to be any visual differences between the two. I suggested that there may be something stamped into the back of the brakes to indicate front or back; and he is going to take one of them off and check this out.

So is there a way to know which one is the front or rear?

I checked Shimano's website and couldn't find anything other than their statement about them being "front and rear specific" -- the PDF specifications make no mention how to tell them apart.

[dirtdigger88]

keith- I sold mine to SoCalSteve- but going off of memory- I could swear the two brakes DID HAVE different length bolts- like they seem to have for years-

other than that- I remember looking at the two trying to figure out the differences- but couldnt see any other than the post

Jason

[William]

keith- I sold mine to SoCalSteve- but going off of memory- I could swear the two brakes DID HAVE different length bolts- like they seem to have for years-

other than that- I remember looking at the two trying to figure out the differences- but couldnt see any other than the post

Jason

Ditto. Could it be that he got two of the same? F/F or R/R.


William

[dirtdigger88]

so what is it Keith-

short bolt - rear

long bolt - front

I guess the best case it two fronts- so you could cut down the bolt to work in the rear-

Jason

[Keith A]

Ditto. Could it be that he got two of the same? F/F or R/R.This was my suspicion as well, but I didn't know if there was any other way to tell other than different length brake bolts. Since Shimano is good about stamping their part number on everything, it would make sense to me that they would have stamped a "F" or "R" along with the part number. I know they stamp a "L" and "R" on the appropriate pedals and this one is easy to figure out if you get it wrong.

My friend bought the complete build kit from CC and would expect they would exchange it for the correct one.

On a related note, why would you not also what a 25% more rigid brake in the rear as well? I realize that the front brake does most of the work, but it seems like a more rigid rear brake would also improve the stopping and control of the brakes.

[Too Tall]

Blame it on Cain. Weight is prolly the issue and you don't need a super stopper for the back.

Short bolt = rear.

[Keith A]

Just off the phone with my friend and he took off both of the brakes after I spoke with him yesterday and discovered that his recollection of the brake bolts being the same length was incorrect. He had installed these a couple of weeks ago and then was reading Shimano's website this weekend and started wondering if he received the correct brakes as he couldn't remember any differences between the two.

At the time when he called, I couldn't recall if the greater depth on the front was accomidated by a longer nut alone or if the brake bolt was longer too -- and I didn't feel like pulling it apart to find out.

So all is well and I appreciate everyone's hlep!

[The Spider]

if you had suspicions....you could weigh them....the front would weigh a bit more maybe a 162g to 145g sort of deal.

[Squint]

I took a look at my brakes and the brake I have installed in the front is labeled BR-7800. Looking at the rear brake in the same area, I can't find any label or stamping. Strange.